Moving countries is a daunting task for most people. The vast amount of information available, both official and non-official can be confusing and self-contradictory. There are a number of basic steps that need to be taken, if you plan to work in New Zealand, and don't have the legal right to do so (you don't have a work visa).
The first step is a combination of two things. You need to start getting your documents in order. Birth certificates for the kids (and adults if residency is on the cards), marriage certificates, police clearances and medicals, although the latter should not be done until closer to the time that a job is offered.
At the same time, applicants must begin their search for work. This might include having their CVs looked over by a professional, or getting in contact with recruitment agents (many of whom won't work with non-visa holders). A lot of applicants would benefit from a written eligibility assessment, demonstrating that there is very little chance any hiccups will arise when it comes time to get their visas processed. This gives the employer a bit of confidence that they haven't wasted their time on you.
Once your visas are lodged, it may be time to look at what's involved in the physical move. Investigating shipping or "cube" options, flight prices, accommodation arrangements for the first few weeks, and the cost of living. See the linked cost of living calculator;
It is important to note however that people should not begin to sell their homes and resign from their jobs, until they have received their visas. This is because those visas may be declined, leaving you in a very difficult position financially.